package cn.yunyichina.openapi.sdk.security;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class AesEncryption {

    public static String encrypt(String data, String key, String iv)
            throws Exception {
        try {

            Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
            int blockSize = cipher.getBlockSize();

            byte[] dataBytes = data.getBytes("UTF-8");
            int plaintextLength = dataBytes.length;
            if (plaintextLength % blockSize != 0) {
                plaintextLength = plaintextLength
                        + (blockSize - (plaintextLength % blockSize));
            }

            byte[] plaintext = new byte[plaintextLength];
            System.arraycopy(dataBytes, 0, plaintext, 0, dataBytes.length);

            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());

            cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
            byte[] encrypted = cipher.doFinal(plaintext);
            return Base64Method.encryptNormalBase64(encrypted);

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    public static String desencrypt(String data, String key, String iv)
            throws Exception {
        try {

            byte[] encrypted1 = Base64Method.decryptNormalBase64ForByte(data);
            Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());
            cipher.init(Cipher.DECRYPT_MODE, keyspec, ivspec);
            byte[] original = cipher.doFinal(encrypted1);
            String originalString = new String(original, "UTF-8");
            return originalString;

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}
